Famous for portraying "Dog" in the 1998 feature Lock, Stock and Two Smoking Barrels and Billy Bright in the 2004 English movie The Football Factory, he is also notable for his guest spots on television series such as Waking the Dead, Doctors, and The Bill.
Early in his acting career, he played the role of Mickey in the 1988 Denzel Washington crime movie For Queen and Country.
He appeared in the music video for The Streets' song "Fit But You Know It."
He was raised in Downham, South East London, England. His father, professional footballer Dave Harper, played for the Millwall F.C. in the late 1950s and early 1960s.
He played Keira Knightley's character's father in the hit 2002 movie Bend It Like Beckham.